Telemarketers, pollsters, wrong numbers, etc., are distracting and, in some instances, the callers may misrepresent the company or organization for which they work. For instance, callers may misrepresent their identity or other information in an attempt to phish private personal or financial information. For example, a caller might represent that they are from the internal revenue service (IRS) and may ask a callee for their private information, such as their social security number (SSN).
There is little that a callee can do to protect himself from these types of attacks, because a fraudulent caller may imitate the voice characteristics of a person known to the callee, may spoof a fake caller ID, or otherwise pretend to have a particular identity or be from a particular organization.
While some techniques for identifying the caller exist, these existing methods can be easily spoofed by a sophisticated fraudulent caller. For instance, some such existing techniques for detecting fraudulent callers include voice recognition, checking a caller ID, or tracing telephone calls. However, even if a phone route is known, there is no asserted information that this specific phone at that specific location actually belongs to this specific organization. Similarly, while some existing techniques detect keywords in conversations and determine that a conversation is potentially fraudulent based on the keywords, these systems result in a large number of false positives because they cannot reliably verify the keywords for legitimate calls.
While techniques for verifying websites and phishing e-mails exists, these existing techniques are not directly applicable for phishing or spam phone calls. For example, unlike the case of Secure Sockets Layer where a browser requests a webpage and matches a certificate to a webpage, a receiving phone does not initiate the phone call, but rather receives it, so the identity of the caller or attributes of the call cannot be verified by the callee, but must be assumed to be accurate. Therefore no satisfactory techniques exist for detecting and preventing spam, phishing, or other fraudulent phone calls.
It is desirable to address these issues.